The present invention relates to spinal osteosynthesis devices for interconnecting vertebral bodies such as thoracic vertebrae or lumbar vertebrae, etc., and, more particularly, to a vertebral connecting rod and a spinal osteosynthesis device using the same.
In recent years, it has been a usual practice to employ a spinal osteosynthesis device which includes spinal implants, each of which has a U-shaped engagement recess, anchored to separated vertebral bodies such as thoracic vertebrae, lumbar vertebrae etc., and a vertebral connecting rod which has distal ends rigidly supported by screwing fixture plugs into the respective spinal implants.
Further, it has been proposed to anchor the spinal implants to the separated vertebral bodies, with one of the implant having a head portion formed with an L-shaped hooking segment for hanging an interconnecting member such as an artificial ligament, a wire or a cable, etc., for thereby interconnecting the vertebral bodies such as the lumbar vertebrae.
Consequently, in the event that one osseous interconnecting structure employing the vertebral rod and another osseous interconnecting structure employing the interconnecting member are located in a series, it has been a usual practice to anchor one of the spinal implants, which rigidly supports the distal ends of the vertebral connecting rod, and another spinal implant, which hangs the interconnecting member, into a common vertebral body in close proximity relationship.
As a result, the spinal implant, which rigidly supports the vertebral connecting rod, and the spinal implant, which hangs the interconnecting member, are subjected to mutually interfering with one another while disturbing the operation of a manipulation tool for screwing a fixture plug into the spinal implant. Another severe issue is encountered in the above practice in that the presence of the two spinal implants anchored to the common vertebral body exerts a significantly large load thereto.
The present invention has been made with a view to overcoming the various disadvantages encountered in prior art devices and it is therefore an object of the present invention to provide a vertebral connecting rod and a spinal osteosynthesis device using the same.
According to a first aspect of the present invention, there is provided a vertebral connecting rod for interconnecting vertebral bodies, which comprises a pin-shaped section rigidly supported by one of spinal implants anchored to the vertebral bodies, and a hooking segment formed on at least one of distal ends of the pin-shaped section, wherein the hook segment serves to hang an interconnecting member hanged to another one of the spinal implants anchored to the vertebral bodies.
According to a second aspect of the present invention, there is provided a vertebral connecting rod which further comprises a slip-out protective member engageable with the hook segment for preventing the interconnecting member, which is hanged with the hooking segment, from slipping out from the hook segment.
According to a third aspect of the present invention, there is provided a vertebral connecting member, wherein the pin-shaped section has at its arbitrary position formed with an engagement convex segment engageable with an engagement concave recess formed in the one of the spinal implants.
According to a fourth aspect of the present invention, there is provided a vertebral connecting rod, wherein the hook segment has a U-shaped hanging recess.
According to a fifth aspect of the present invention, there is provided a vertebral connecting rod, wherein the U-shaped hanging recess has an entrance portion formed with a pair of engaging protrusions.
According to a six aspect of the present invention, there is provided a vertebral connecting rod, wherein the pair of engaging protrusions have distal ends formed with outwardly extending minute projections, respectively.
According to a seventh aspect of the present invention, there is provided a vertebral connecting rod, wherein the slip-out protective member comprises a slid cap having slide recesses engageable with the minute protections, respectively.
According to an eighth aspect of the present invention, there is provided a vertebral connecting rod, wherein the slip-out protective member is coupled to or uncoupled from the minute projections along longitudinal directions thereof.
According to a ninth aspect of the present invention, there is provided a vertebral connecting rod, wherein the slip-out protective member is coupled to or uncoupled from the minute projections in a direction perpendicular to a longitudinal axis of the pin-shaped section.
According to a tenth aspect of the present invention, there is provided a vertebral connecting rod, wherein the hook segment has a substantially L-shaped configuration.
According to an eleventh aspect of the present invention, there is provided a vertebral connecting rod, wherein the L-shaped configuration has a distal end formed with an engaging protrusion.
According to a twelfth aspect of the present invention, there is provided a vertebral connecting rod, wherein the hook segment has a substantially U-shaped configuration.
According to a thirteenth aspect of the present invention, there is provided a vertebral connecting rod, wherein the U-shaped configuration has an entrance portion formed with a protrusion extending in a direction to close the entrance portion.
According to a fourteenth aspect of the present invention, there is provided a spinal osteosynthesis device for interconnecting vertebral bodies, which comprises a pair of spinal implants adapted to be anchored to the vertebral bodies to be interconnected, a hooking spinal implant adapted to be anchored to the vertebral body, a vertebral connecting rod rigidly supported by the pair of spinal implants and having its one end formed with a hook segment, and an interconnecting member adapted to be hanged between the spinal implant and the hook segment of the vertebral connecting rod.
Thus, in on aspect, the present invention is directed to a vertebral connecting rod for interconnecting vertebral bodies, comprising an elongated section including distal ends, the elongated section being capable of being rigidly supported by a spinal implant; a hook segment formed on at least one of the distal ends of the elongated section, the hook segment serving to hang an interconnecting member capable of being connected to another spinal implant; and the elongated section including an engagement convex segment at an arbitrary position which engagement convex segment is capable of being engaged with a corresponding engagement concave recess formed in a spinal implant.
In another aspect, the present invention is directed to a vertebral connecting rod for interconnecting vertebral bodies, comprising an elongated section including distal ends, the elongated section being capable of being rigidly supported by a spinal implant; a hook segment formed on at least one of the distal ends of the elongated section, the hook segment including a U-shaped hanging recess serving to hang an interconnecting member capable of being connected to another spinal implant; and a slip-out protective member engageable with the hook segment for preventing the interconnecting member, when hung in the hook segment, from slipping out of the hook segment.
In still another aspect, the present invention is directed to a vertebral connecting rod for interconnecting vertebral bodies, comprising an elongated section including distal ends, the elongated section being capable of being rigidly supported by a spinal implant; a hook segment formed on at least one of the distal ends of the elongated section, the hook segment including an L-shaped configuration serving to hang an interconnecting member capable of being connected to another spinal implant; and the L-shaped configuration comprising a distal end formed with an engaging protrusion.
In still another aspect, the present invention is directed to a spinal osteosynthesis device for interconnecting vertebral bodies, comprising a pair of spinal implants adapted to be anchored to vertebral bodies to be interconnected; a hooking spinal implant adapted to be anchored to the vertebral body; a vertebral connecting rod rigidly supported by the pair of spinal implants and having one end formed with a hook segment which includes a U-shaped hanging recess; and an interconnecting member adapted to be hanged between the hooking spinal implant and the hook segment of the vertebral connecting rod.
Other aspect and advantages of the invention will become more apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.